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terception of communications in Title III of the Omnibus Crime Control and Safe Streets Act of 1968 (Title III). In 1986, the Electronic Communications Privacy Act (ECPA) made significant additions and amendments. Title III, as amended by ECPA, defines three categories of communications—oral, wire, and electronic—and provides varying degrees of legal protection against their unauthorized interception. Oral communications are spoken words carried by sound waves through the air. Electronic surveillance of oral communications is performed with listening devices, known as bugs. Wire communications are human speech carried over a wire or wire-like cable, including optical fiber. They may be intercepted with a wiretap. (Interception of one end of a conversation by bugging the room in which a telephone is placed is a case of oral interception.) Electronic communications are defined—with minor exceptions such as toneonly pagers—as every other form of electronically transmitted communication, including various forms of data, text, audio, and video. The legislative history of ECPA specifically mentions electronic mail, paging systems, bulletin board systems, and computer-to-computer communications, among other technologies the act was intended to address.3

ECPA defines radio communications, including voice conversations, as electronic, with the exception that voice conversations carried in part over radio and in part through wires or switches (such as cellular telephone calls) are treated as wire communications.4 Some radio communications may be intercepted without penalty. Courts have found, and ECPA affirms, that if a radio transmission is readily accessible to anyone with an appropriate receiver, it does not meet the Fourth Amendment test of a "reasonable expectation of privacy" and is therefore unprotected.5 However, ECPA specifies several forms of radio communication that are not "readily accessible" and therefore are protected from interception. These include, among others, encrypted or scrambled transmissions (digital modulation alone does not meet this standard, unless the protocols have been deliberately concealed from the public to maintain privacy); common-carrier paging services (except tone-only services); and private microwave services. In practice, unprotected radio transmissions generally relate to radio broadcasting, dispatching, public-safety radio (police, fire, etc.), amateur radio, citizens band, and similar services. In the radio

3 Fishman, Cumulative Supplement, 1994, sections 7.31-7.49.

4 Fishman, Cumulative Supplement, 1994, sections 7.4, 7.5, 7.21-7.28. See also James G. Carr, The Law of Electronic Surveillance, Clark Boardman Callaghan, Deerfield, III., September 1994, section 3.2.

5 By similar reasoning, messages are unprotected if posted in electronic bulletin board systems that are configured to make such messages readily accessible to the general public. Fishman, Cumulative Supplement, 1994, section 7.67.



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